A Spring in the Desert: Infertility and Merciful Accompaniment.

The mystery of love as it unfolds in marriage is an adventure filled with wonder and anticipation for what the future holds. Such is the excitement and optimism of the couple embarking on family life by actively trying to conceive a child. For the couple struggling with infertility, however, joyful anticipation can soon devolve into anguish as they realize that their hoped-for children might not come.

High acidity tolerance in lichens with fumarprotocetraric, perlatolic or thamnolic acids is correlated with low pKa1 values of these lichen substances.

The depsidone fumarprotocetraric acid as well as the depsides perlatolic and thamnolic acids are lichen secondary metabolites. Their first dissociation constants (pK(a1)) in methanol were determined to be 2.7 for perlatolic acid and 2.

Dissociation and metal-binding characteristics of yellow lichen substances suggest a relationship with site preferences of lichens.

Background And Aims: Many species of lichen-forming fungi contain yellow or orange extracellular pigments belonging to the dibenzofurans (usnic acid), anthraquinones (e.g. parietin) or pulvinic acid group.

Lichen substances affect metal adsorption in Hypogymnia physodes.

Lichen substances are known to function as chelators of cations. We tested the hypothesis that lichen substances can control the uptake of toxic metals by adsorbing metal ions at cation exchange sites on cell walls. If true, this hypothesis would help to provide a mechanistic explanation for results of a recent study showing increased production of physodalic acid by thalli of the lichen Hypogymnia physodes transplanted to sites with heavy metal pollution.

Ketamine enantiomers differentially relax isolated coronary artery rings.

Background And Objective: It has been shown that racemic ketamine increases coronary blood flow and that this effect is at least in part due to a direct vasorelaxing effect of this substance. This study was designed to determine whether ketamine might stereoselectively relax isolated porcine coronary arteries.

Methods: Using the model of isolated vessels we studied the effects of S(+) ketamine, R(-) ketamine, and racemic ketamine (5-500 microg mL(-1)) on artery strips pre-contracted by either potassium chloride (KCl) or prostaglandin F2alpha (PGF2alpha).